Method of updating the display of electrophoretic display mechanism and the device thereof

Abstract

A method for driving an electrophoretic display device for reducing the time required to update the display image. The electrophoretic display device comprises a frame buffer, a lookup table, a controller and an electrophoretic display panel. The frame buffer stores a first display frame data. The controller accesses a transition data of transforming the first display frame data to a second display frame data according to the lookup table, for outputting a control data. The electrophoretic display panel displays the second display frame data according to the control data. Therefore, the position the charged particle in a pixel to be moved to during the erasing step can be adjusted by utilizing the lookup table, consequently reducing the time required to update the pixel.

1 . A method for driving an electrophoretic display (EPD) device, the method comprising:
 writing a first grey level to a first pixel;   when the first grey level is closer to a grey level of complete black, erasing the first grey level to the grey level of complete black;   when the first grey level is closer to a grey level of complete white, erasing the first grey level to the grey level of complete white; and   writing a second grey level to the first pixel after the first pixel is erased.   
     
     
         2 . The method of  claim 1 , further comprising:
 providing a lookup table of transition data for transforming grey levels.   
     
     
         3 . The method of  claim 2 , wherein when the first grey level is closer to the grey level of complete white, erasing the first grey level to the grey level of complete white comprises:
 obtaining a transition data of transforming the first grey level to the grey level of complete white according to the lookup table; and   erasing the first pixel according to the transition data of transforming the first grey level to the grey level of complete white.   
     
     
         4 . The method of  claim 2 , wherein when the first grey level is closer to the grey level of complete black, erasing the first grey level to the grey level of complete black comprises:
 obtaining a transition data of transforming the first grey level to the grey level of complete black according to the lookup table; and   erasing the first pixel according to the transition data of transforming the first grey level to the grey level of complete black.   
     
     
         5 . The method of  claim 4 , wherein writing the first grey level to the first pixel comprises applying a positive voltage to the first pixel for a first duration, and writing the second grey level to the second pixel comprises applying the positive voltage to the second pixel for a second duration. 
     
     
         6 . The method of  claim 5 , wherein erasing the first grey level to the grey level of complete black comprises applying a negative voltage to the first pixel for the first duration, and erasing the first grey level to the grey level of complete white comprises applying the positive voltage to the first pixel for a third duration. 
     
     
         7 . The method of  claim 6 , wherein the positive voltage, the negative voltage, the first duration, the second duration and the third duration are stored in the lookup table. 
     
     
         8 . A method for driving an EPD device, the method comprising:
 writing a first grey level to a first pixel;   erasing the first grey level to a predetermined grey level between a grey level of complete white and a grey level of complete black; and   writing a second grey level to the first pixel after the first pixel is erased.   
     
     
         9 . The method of  claim 8 , wherein the predetermined grey level is a middle grey level between the grey level of complete white and the grey level of complete black. 
     
     
         10 . The method of  claim 9 , further comprising:
 providing a lookup table of transition data of transforming grey levels.   
     
     
         11 . The method of  claim 10 , wherein erasing the first grey level to the predetermined grey level between the grey level of complete white and the grey level of complete black comprises:
 obtaining a transition data of transforming the first grey level to the predetermined grey level according to the lookup table; and   erasing the first pixel according to the transition data of transforming the first grey level to the predetermined grey level.   
     
     
         12 . An EPD device, the EPD device comprising:
 a frame buffer, for storing a first display frame data;   a lookup table;   a controller, electrically connected to the frame buffer and the lookup table, for obtaining a transition data of transforming a first grey level of the first display frame data corresponding to a first pixel to a second grey level of a second display frame data corresponding to the first pixel from the lookup table, and outputting a control data accordingly; and   an EPD panel, electrically connected to the controller, for displaying the second grey level of the second display frame data according to the control data.   
     
     
         13 . The EPD device of  claim 12 , further comprising:
 a DC/DC converter, electrically connected to the EPD panel, for providing driving voltages to the EPD panel.   
     
     
         14 . The EPD device of  claim 13 , wherein the lookup table is utilized to store the transition data for the first grey level corresponding to the first pixel to transform to the second grey level corresponding to the first pixel.